The plot of "I Know Who Killed Me," a coldly ludicrous thriller starring Lindsay Lohan, is so goofily convoluted that I took a tour of various movie-spoiler sites after watching the film, just to clarify the chronology of events. Looking at the movie's page on Screenit.com, that consistently laughable guide for worried parents, I found this gorgeous line: "Dakota uses her robotic prosthetic arm to break the glass on the top of a coffin." How can you possibly screw up a movie in which that happens?

Easily. First you hire a director, Chris Sivertson (who co-helmed All Cheerleaders Die with Lucky McKee), who treats the goddamn thing with utmost solemnity. And not the kind of solemnity that invites unintentional hoots; the boring kind that wants desperately to find art and meaning in this schlock. Sivertson, I'm guessing, has seen his share of Dario Argento, judging from the preponderance of color-coding throughout the movie. Good girl Aubrey Fleming (Lohan) is identified with blue. Bad girl Dakota Moss (also Lohan) is all about red. Are these girls the same person? Could Aubrey, a conscientious student who regretfully gives up piano lessons to concentrate on her writing, be the same person as Dakota, a coarse stripper? Or is Dakota Aubrey's id playing itself out in delusional, self-protecting fiction? Or is Aubrey Dakota's dream vision of the way her life should have gone?

You get all the answers eventually, in a half-baked torture-porn plot in which Aubrey is kidnapped and tortured, then winds up in a ditch with an arm and a leg gone. When Aubrey wakes up in the hospital, she insists she's Dakota. Her parents (Neil McDonough and Julia Ormond) know she's Aubrey, because this girl looks just like her; but this girl tells a different story, of being brought up by a crack whore and selling her body to make ends meet.

So: madonna and whore. One would've thought the familiar sexist duality was put to rest in the movies of David Lynch, particularly Twin Peaks: Fire Walk With Me, in which Laura Palmer was both. I can see why Lindsay Lohan was drawn to I Know Who Killed Me: it gave her the chance, she must've thought, to kiss her wholesome Disney image goodbye forever and play two extremes in the same movie. And to be honest, she isn't bad here; whatever else is wrong with the film, Lohan plays Dakota — who gets most of the screen time — with a hard-bitten exhaustion and a quick, salacious wit. The tabloids may make us forget that beneath all the foolish, self-destructive behavior is a young woman with actual talent and natural charisma. Dakota often seems like the only person in the movie with any common sense.

That's about the only time the words "common sense" can appear in a review of I Know Who Killed Me, which comes complete with ominous owls, blue roses, a cellar filled with mannequin parts (shades of Kubrick's Killer's Kiss), and a scene in which Julia Ormond, as the mother going borderline nuts trying to figure out why her innocent daughter is now a chain-smoking slut, angrily scrubs the kitchen sink downstairs while Dakota jumps the willing bones of Aubrey's boyfriend. Ormond, who had a small but alarming role in Lynch's Inland Empire last year, seems to want to leave her empty romances behind and be reborn as Charlotte Rampling; age has tightened her features, given her a new, hungry intensity. She seems to want to be in the wild, over-the-top thriller that I Know Who Killed Me should've been but isn't. (Another Lynch footnote: Bonnie Aarons, who played the notoriously terrifying alley bum in Mullholland Drive, shows up here as Dakota's dyspeptic strip-club boss, known as Fat Teena. With this kind of cast, the movie should've been a lot more lovably ridiculous.)

The torture bits are fairly grotesque at times, killing our fun. The idea of a serial killer who carefully removes limbs with dry ice is so absurd that to see it enacted in diffuse close-up is an unnecessary turn-off — the movie isn't a serious treatise on violence against women, after all. Sometimes I suspected the shots of Lindsay Lohan bound, gagged, and screaming were thrown in there to appease the Lindsay-haters, the way Demi Moore's ordeals in G.I. Jane seemed designed to stroke the Demi-detesters in the crowd. If the press doesn't like you, do your penance by being taken apart in movies. It seems to have worked for Mel Gibson (who has moved on to dismantling other people in the movies he directs).

I knew I Know Who Killed Me would be stupid and bad, but I wanted it to be gloriously bad, camp-classic bad, and the movie is too ineptly artsy and unpleasant to make it. And Lohan's sincerity in the role(s) works against it: she keeps her scenes real, when what's needed is flailing and shrieking. This is the kind of movie that should rival Juno in the length of its "Memorable Quotes" page on IMDb, but the best line on its page is "Do I look like I'm in a fucking coma?" No, Lindsay, you don't. And this is too obviously and sadly an attempt on Lohan's part to reconcile her Ivory-pure screen persona with her increasingly blotto reputation in the tabloids; as it turns out, the white-trash whore with a dirty mouth turns out to be the hero, roundly defeating the villain and saving the virgin. Lohan may be saying that she can be trashy and still be a good person.

Years from now, the movie will likely be more interesting as a case study or a snapshot of a gifted but terribly troubled starlet at (let's hope) her personal and professional nadir. Right now it plays like a flat miscalculation, too ugly to be goofy fun and too inextricable from a real person's problems to be laughed off.